Rub rail assemblies of the kind with which the present invention is concerned typically include a somewhat shock absorbent extruded rub rail, made of a material such as rubber or resilient plastic, and an extruded metal channel strip support to which the rub rail is appropriately attached. Rub rail assemblies of this kind are used principally to protect wall surfaces, equipment, etc. which in ordinary use are subjected to repeated frequent and abusive impacts or abrasions, such as vehicle doors and fenders, marine docks, supermarket checkout counters and cases including refrigeration-cases, shelving, display tables, refrigeration equipment, etc.
Typically, rub rail assemblies known today (see FIG. 1 of the drawings and the patents to Rubin et al U.S. Pat. Nos. 4,083,592 and McCue et al 4,808,451) include a rub rail supporting channel strip 1, and a hard rubber or plastic rub rail extrusion 2 secured to the channel strip by means of a pair of hollow leg members 3,4 or other such interlocking elements. A metal end cap 10 having a protective shell 12 is located at and attached to each end of the channel strip 1 via the insertion of a pin member 14 into a recess 8 of the channel strip 1. Each of the hollow leg members of the rub rail extrusion are deformably engaged with a correspondingly configured rigid jaw 5,5' or 6,6' disposed on the channel strip. The channel strip 1, like the impact absorbing rub rail extrusion 2, is typically provided as an elongated member, with the rub rail 2 overlying the channel strip and being cut or otherwise terminated in a length which is substantially the same length as the channel strip or in a plurality of pieces.
The end caps 10 are generally employed to cover the ordinarily unsightly, unfinished, approximately aligned, overlying ends of the channel strip and the rub rail extrusion, as well as to provide the entire rub rail assembly with a tailored and aesthetically pleasing appearance. The end caps 10 also anchor the ends of the rub rail 2 to the channel strip 1.
One of the more common problems encountered in the use of end caps with rub rail assemblies is that the heights of the installed rub rails and end caps are normally not the same. It is not commercially possible to produce rub rail extrusions with a consistent excellent appearance in various colors using, as necessary, an unbalanced die, while at the same time providing close dimensional tolerances, unless a very rigid plastic is used; however, the use of rigid plastic is successful only if very expensive plastic such as polycarbonate is used. In particular, it would be desirable to have the height of the rub rail extrusion equal to, or exceed by no more than from about 0.005" to about 0.015", the height of the end cap while using inexpensive, shock absorbent plastic. The industry's present manufacturing processes do not lend themselves to providing components, both end caps and rub rail extrusions, with heights that consistently fall within the tolerance ranges considered necessary for uniformity in this industry.